SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '740949cf846c9efb67a8461d1373c567b0430be8ec04d3aacd78c7cd3f58ef12' 
  AND token = 'DD3rZgGfmpe9pJd3nYufqBj1hhQ5zCh7loiDGqmcOUM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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