SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1f063a0df9489053a1437705e8b62bf7615208ce23cd8932ab90f6305bffec67' 
  AND token = 'NghThYLqKbcoqLUBBXRTJ1n2TPoYPmuU2E5z7cAuSUg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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