SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '80b3c2bfaf46f097275d2f4eea2a62f6b6ab71e3aec4368c9141f64770fe5fca' 
  AND token = 'N1Gwlv4QIDEjUuzC6SHMPkOXDqBmpSgfZVYUYqVjhwo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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