SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cd9298841c051b99f4b376d0fcdbf0793f00e2b4b8a88c12a23e8aa0fbbc4424' 
  AND token = 'IcYwW4xuKkQxDSPFNaEHrIGnwMMppSCVAd6xwia62v4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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