SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c37be1ca543fcffa0a13bfacb9d15faf5db817fa36cdc41ac24df85a7ea5d3f3' 
  AND token = 'U/WccUwQv/rZRZBn46FcxFThU689p29qphlzauqOnEA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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