SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0ce8ecf66d1642a6a396d5beddc229a3a4b77a1b4c850da993cf24f27cd9148f' 
  AND token = 'LtM3BWdktRQfAMKEQ5XAaswvlqkfvsbytNlwWTYE2U8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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