SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4fd4617be6467d4ff555cb95de650e3646a422bfbce855c9df70490e93c45f5e' 
  AND token = '6fL+0A14u3CneBhZc3r5JwViARSWVl6Po7C3BSC+OUk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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