SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1724e723f15aba88e0212ede97ed06326b820bf9a1480d0373466e20c7f33556' 
  AND token = 'EqpKIeMztGU7VkYfShhVB1HeRASeOOzUaXG7zu8Vcic=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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