SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ea89fc42b1702008d7ab6c5c65dd5b7344a016226e74fca7633a2b0d133db0cf' 
  AND token = 'axvpK/sbvqzALoGvi0M2QDqjfRNgvZqmXEMdlCPP39Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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