SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c98750a785d067d6678e3d36057a874a0638006a9e8ccbb926652bd4832e3c96' 
  AND token = 'eypPvbL8MyXEYndtQ1mgV7PXGLmnFUUKOTpBUlvKuhg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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