SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cce4248c272451b4ccbf57af0f2ea3e867bab1120fe5d72cb9efda4ac6811f08' 
  AND token = 'ehDqlpP2UBbX334CWhCIEh+dgrLeNzBDIqUu9NZshiU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

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