SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'fe86a898359394627703aeb709457cacefe7e37f0e7cca3f520b937da0354a44' 
  AND token = 'fbwL+0NtdIWhAwdu9Y3Nkwyin6YnDacPsG8+VO3md1Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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