SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b40aadafbc5c00c095aed70b3a2123917c9e9a397d2245c534d394ca076c51c6' 
  AND token = '4ZyVsZImDCLtbCTIohcQ95myb90ljqw9vlWAaix8aNg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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