SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '53f267db74300bdd7c11a197cac133ecf570bcebf3a0e186a57acb07fa0eaa82' 
  AND token = 'kcbVFUKhWGIBtFo+kvSNom1rJZ7nu8r2kc76wtrHAs4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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