SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8969ea1f0add2534c7f3a725c5b74b119a48d7f209de899d1a3aebaf0a0b3cfc' 
  AND token = 'jc/MMJbDIMNz00jmaNt8SVkjAuWC2d7Ddz2HShFLdxQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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