SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fe0a6d4444373bf3a0ae71c6bf32ca96ad7712e46b46baf9b4fe9a001d02d3b4' 
  AND token = 'yD2ISUvtdyC7NUZL+b/Gdu/ACk1K9BPDSniiEkGLBKs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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