SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'eadc7becf979f764417e53d1e23fc6c746c68ea21fe733565eecf45dc745ac97' 
  AND token = 'fSK9ACdXWqvVIXSJD7+ztjPPUdGEme+ovm8iFRpYDM8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00102

JSON explain

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