SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fccc59d7e4251e5c419b4708c40c9ea0910b13dde170ee06b186f515bc9774d1' 
  AND token = '23tiTX2igalF2kOO/RtPaU/1FaS2jIPbGVg/+ggMpOI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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