SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8071c382fe9d5ea1817522dc44acaeb06f4fdcbcf158e206ebf51911e9ea7bce' 
  AND token = 'mN9HjseHaliPkTyYYbmNEY409gZjWtl9Z8qdh5B87nY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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