SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '59386005f5d8f2374e3dcca91a0eaaa8cfc0bc4fe2566f19ced2765b0b45fbf6' 
  AND token = 'RFjUNQYoeYISGIKkqLKHKvew1JIrp5HhnSjB0WUom7k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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