SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1752f0f5d264b889a6dd0f14eaecc1fa71d1df60c916c936c5d3b779195f4e38' 
  AND token = 'PPuZwYDLFdqKvgOV/C56xkH/xnX8xb8uTTJL5Z2getY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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