SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f430f8aa8573fd8faeb8eab5184bd714dd873e11f02ffc82b137aa367cea8373' 
  AND token = 'te2J146naPp/09C+/Qs68PvvUR35YxumZuSBJGwDFIU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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