SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4902569a473df207d8e4043599345cdabf10b0627b3b4e8b119f09c44f5bc1be' 
  AND token = 'zVPec92QTpe323ewnqVd1tkD4P4wG2Cn0PkE8a4817c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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