SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '111f347d2bc033d1e7be37767f79da1e1d01255cef8d5bb753332f6c8c920528' 
  AND token = 'bXgD7yyuhzPwB+mmrfjcUWAV2FqMywRmAcPluQV3kjM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}