SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'eb77e92852c2a1299755dbb8a0b01cbef8d530480b042ce9698bd673d2b56ff1' 
  AND token = 'EMWL+14VaxmYFqRqGzLPpFs/2u4j/thpGXsKOlTNC/k=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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