SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ede4d72207387fa2abf1d715bb9251b94f2296f778f1b3de7ba2e408be975f77' 
  AND token = 'mWX1SKzwHbVYL7KTyl/vX75f/Y13xyN6Y5HuCf/1cCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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