SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e032485f3516e71b673a17c766841635dd6f852ff2af1d47633d061c1f43b6cc' 
  AND token = 'p+sSy06/MSq9Lf49UF9P0sePFNJPX7xQrUpSozW7Cnw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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