SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fc60350617c6fbd611c166c190860c638037bf0a48e4ade19cf137127f9fe8d7' 
  AND token = 'bbDwbRmzkXT2UeiHIJ2T3EN92lr85aoXnKBjKv6UrZ0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00060

JSON explain

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