SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '65f63972f4033653e0b51acbab2e8f620e17cf2fb50f437576c0dbdb52aa31c9' 
  AND token = '2voJ6ku1n5upRtuHh6ODaGptBQ2MVG1rdKhbytRz9wU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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