SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7a5cc6d4c51ecb094cf1958c7ff243a762148258e2cb000e59948afb149d2932' 
  AND token = 'qWwrXLb/WvlYBz4KOItQsOq0eWlF+d3133wTfwwFjK4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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