SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '69cea129c822fa056cafdc457ce7bf501b0f4f953099ccc5c1c747eff7062c9a' 
  AND token = 'sI3U7Hy5+RKGy1oCxlGxkrsmAxqwMn5RcztVj1bFoTc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}