SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59d3b9d48a97ec0da2e3f1c91754f7f2266d7a8b6a1977eb71b7c6571e8a0f98' 
  AND token = 'tI1Ye9/BCsdJliNlIHlQyo3/23XYH6lV8elzpY4qa50=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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