SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8780273c2dab930bc0418707df3d65f27f811a5c2db97b94eb20015a2627c6e0' 
  AND token = 'pEKbzk31Np6pQTOi8FgGyWdgj1rSFCOZ4Y7uqWCyRCE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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