SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '95c7b600ea7fc2091dcb74855b71d26c0cc66d57be6e0c37ae165baf8644d4ea' 
  AND token = 't0a1sqykoSpEOH5yr3kOqXGlhLQEK1yriQnLK75cSXg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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