SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e7b4895f8d7a78c14f303ba61606b1604e1c6234a1d482b7c7e197f28c5e9960' 
  AND token = 'R+llWkkOeVNmfG/m2lheKdHmH/1RzW4s0eBDqzHUfJg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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