SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5897f0aa23ed680adddb503aaf9d850af247dd5c15353565be51a953df3b21f7' 
  AND token = '4ATiGdR2+pj34LHuLD5w4a9/gRBsD0o31JWbhV0Zq5w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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