SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ce2762cc7f07c1e989afeff84119c73fed6e1628b4aaeb507b1ca41005466592' 
  AND token = '+kV2C/6yupxSaGUqJ1nLfaSP3W973C/2NjtBFwHVMqE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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