SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e19f3991e6c6d995fc0eeacf0bd7435ba183803140bb8ae470cd0f6e34897708' 
  AND token = 'BifGdHz8c3TEf4tubHSFIkLrs+tRF6oY2ySNwW5Itvg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00045

JSON explain

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