SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '376d71219012a27be289901b034bbe170ea90fa4c5071df2836bf5c81f6b07f5' 
  AND token = '+Xy8/uc8w5/UTSHGZZtjcMhdzv+HUj/ch06/V0wmpds=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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