SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce36286ea8e36ac2d3ea43a0990dad85edb07597549acb8123e9fe741489daf9' 
  AND token = 'SErL0zNFJtOmMJ2jth/rDntCcR6FlKdoCEvzpojIo4Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}