SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '946d2e1fa9e3bce5da0d4f6de4c2321e950f407e0c84a9de141bdab36809a8dd' 
  AND token = 'aRBpRZBl7qJ8+1Qzc5rSj/SwTQVgwPw6IulNwbEPGZs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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