SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '17845a854b25b6c043102c0745733a638001df3ede087dd6c7091ee2319bcb8f' 
  AND token = 'qFnu+jfpogaseDiQP40mN/qDPDweKv4+CMCYrtExG1g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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