SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cfe0090cff5e9f36498461398cffcfc672dc10d7d21426ce350b5dc83bfbd48a' 
  AND token = 'dHZiDmgxUyyBUofms6yi3Zo5iQmmaLSfNpiKiQXOt24=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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