SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '45fc87f9946a0ab2618a462d8b98e3466cf4464309937ca1eab1832c28c08959' 
  AND token = 'BW0istz6yIHgqn/eokr4Iwt2KNRjLwBqld0ng8HRdnA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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