SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ba95692181512fd54a63f4c3231a28d674ffb0042c2686622032a70b75701382' 
  AND token = 'RLTp+TFpKNFt+1nXDBTkGvoX55xAk+Ru65COz+HBhwQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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